The winter of 1946–1947 was a harsh and bitterly cold winter in the United Kingdom. The UK experienced several cold spells, beginning on 21st January 1947, bringing large drifts of snow to the country, which caused roads and railways to be blocked. Coal supplies, already low following the Second World War, struggled to get through to power stations and many were forced to shut down for lack of fuel. The government introduced several measures to cut power consumption, including restricting domestic electricity to 19 hours per day and cutting industrial supplies completely. In addition, radio broadcasts were limited, television services were suspended, some magazines were ordered to stop being published and newspapers were cut in size. Towards the end of February there were also fears of a food shortage as supplies were cut off and vegetables frozen into the ground. March brought milder weather to the country, and with it the inevitable thaw. What follwed was terrible flooding for parts of the UK.

January 1947
The winter began with two periods of cold weather in December 1946 and January 1947, but the coldest period did not begin until 21st January 1947. The main cause of the cold weather was an anti-cyclone which sat over Scandinavia from 20th January. This high pressure area blocked the progression of low pressure depressions across the Atlantic Ocean and forced them to the south of the United Kingdom resulting in strong easterly winds, which brought snow to Eastern England and South East England before progressing across the entire country. This cold spell continued and by 30th January the Isles of Scilly were under 7 inches (18 cm) of snow and the overnight temperature at Writtle, Essex was −20°C. Over January the highest recorded temperature in England and Wales was 14°C and the minimum was −21°C.

February 1947
The easterly winds continued into February, which developed into one of the coldest months on record. At Kew Observatory there was no recorded temperature above 5°C for the month and only twice was the overnight temperature above 0°C. Nationally, levels of sun recorded were less than half the average and no sun at all was recorded at Kew for twenty days from 2nd February. On 20th February the ferry service across the English Channel between Dover and Ostend was suspended due to pack ice off the Belgian coast. In some places snow fell on 26 days out of 28 in the month and a temperature of −21°C was recorded at Woburn, Bedfordshire on 25th February. As a result, railways were badly affected by drifts of light powdery snow and 300 main roads were made unusable. Several hundred villages were cut off. Ice floes were also seen off the coast of East Anglia, causing a hazard to shipping.

This cold weather exacerbated the fuel problem. Stockpiles of coal at the pits and depots froze solid and could not be moved. The stockpiled coal was often unavailable with roads out of use and 750,000 railway waggons of coal trapped by the snow. Desperate attempts were made to get fuel to power stations by coal-carrying ships which risked storms, fog and ice to reach their destination. A force of 100,000 British and Polish troops and German PoWs were put to work clearing snow from the railways by hand. Despite this, lack of fuel forced many power stations to shut down or reduce their output. The Royal Navy launched Operation Blackcurrant, which used diesel generators onboard submarines to provide supplementary power to coastal towns and dockyards.

Shinwell acted to reduce consumption of coal by cutting the electricity supply to industry completely and reducing the domestic supply to 19 hours per day across the country. In consequence factories across the country were forced to shut and up to four million people claimed unemployment benefits. Although so many people were made redundant there was little unrest and no major public disorders. Television services were suspended completely, radio broadcasts were reduced, some magazines were ordered to stop being published, and newspapers were cut in size to four pages. Food rations, still in use from the Second World War, were cut to levels lower than in the war years. These measures made little difference to the rate of coal consumption but served to reduce public morale.

Despite Shinwell's actions the fuel supply remained insufficient and blackouts occurred across large swathes of the country with even the staff at Buckingham Palace, the Houses of Parliament and London's Central Electricity Board reduced to working by candlelight. A trade meeting with representatives from Russia and Iceland was also forced to meet without light or heat, ironically one of the items discussed was the purchase of coal from Britain. The public was reduced to queueing at gasworks to collect coke for use as fuel. Supplies of aspirin also ran low as it was then a product of coal-tar, thousands of chickens in poultry farms died of the cold, and public transport services were cut to save fuel. Shinwell became increasingly unpopular with the general public and received a bomb threat which meant that he had to be guarded at his house in Tooting by four policemen. Despite this, he remained very popular with the miners, which made the government wary of firing him in case it caused industrial action. By 27th February sea conditions had improved and more than 100 coal ships had managed to unload their cargoes at the power stations, easing the fuel crisis.

During this period there was a fear that, despite the rationing, food supplies could run out, and several measures were taken to prevent this. This due to the effects of the cold on vegetables, livestock and delivery vehicles. The government started a campaign to popularise Snoek, an inexpensive South African variety of fish. This campaign was largely unsuccessful as the public found the fish unpalatable and the stocks of it were eventually used as cat food. Many winter root vegetables could not be harvested as they were frozen into the ground, and in some areas pneumatic drills were used to excavate them. Frost destroyed 70,000 tons of potatoes and, as a result, they were rationed for the first time.

March 1947
On 4th and 5th March came heavy snow which left drifts across much of the country with some lying 7 metres (23 ft) deep in the Scottish Highlands. On 5th March one of the worst British blizzards of the 20th century occurred. Food supplies were again affected by the snow-bound roads and in some places the police requested permission to break into delivery lorries stranded by the snow.

On 10th March milder air began to move north across the country from the south west, rapidly thawing the snow lying on low ground. After such a long frost the ground stayed frozen, causing much surface run off which resulted in widespread flooding. Further heavy snowfalls occurred as the milder air pushed northwards. On 14th March the deepest ever recorded depth of snow lying in an inhabited location was measured at Forest in Teesdale in County Durham at 83" or 211cm. On 15th March a deepening depression moved in from the Atlantic, bringing heavy rain and gales. It was the start of the wettest March for 300 years. By 16th March winds reached 57mph, gusting to 103mph, causing breaches in dykes in East Anglia resulting in the flooding of 100 square miles of land, and blowing many trees down. The River Thames and the River Lea flooded in London causing the Windsor borough engineer Geoffrey Baker to remark "We could only cope if we had a spare Thames, or two".

On 18th March the River Trent, swollen with the extra water which was prevented from emptying into the sea by a spring tide, burst its banks at Nottingham, reaching first floor height. The flooding subsided in the west of the country by 20th March but rivers in the east were still rising and the Wharfe, Derwent, Aire and Ouse all burst their banks in the West Riding of Yorkshire. Selby was also badly affected with 70% of houses being flooded. More than 100,000 properties were affected by the flooding and the Army worked to prevent the spread of the floodwater, particularly at pumping plants and power stations. Royal Engineers on national service handed out milk to families with babies and the Australian Red Cross assisted in Gloucester. The people of Canada sent food parcels to villages in Suffolk and the Premier of Ontario, George A. Drew, offered to help to distribute them personally. The flooding lasted for about a week, with some waters taking an additional ten days to subside.